Function malachite_base::vecs::random::random_ordered_unique_vecs_min_length

pub fn random_ordered_unique_vecs_min_length<I: Iterator>(
    seed: Seed, 
    min_length: u64, 
    xs_gen: &dyn Fn(Seed) -> I, 
    mean_length_numerator: u64, 
    mean_length_denominator: u64
) -> RandomOrderedUniqueVecs<I::Item, GeometricRandomNaturalValues<u64>, I> where
    I::Item: Ord, 

Generates random Vecs with a minimum length, using elements from an iterator, where the Vecs have no repeated elements, and the elements are in ascending order.

Strictly speaking, the input iterator must generate infinitely many distinct elements. In practice it only needs to generate $k$ distinct elements, where $k$ is the largest length actually sampled from the geometric distribution. For example, if mean_length_numerator / mean_length_denominator is significantly lower than 256, then it’s ok to use random_unsigneds::<u8>.

$$ P((x_i)_{i=0}^{n-1}) = n!P_g(n)\prod_{i=0}^{n-1}P(x_i), $$ where $P_g(n)$ is the probability function described in geometric_random_unsigned_inclusive_range, with $a$ equal to min_length and b to u64::MAX.

xs_gen must be infinite.

Panics

Panics if mean_length_numerator or mean_length_denominator are zero, if their ratio is less than or equal to min_length, or if they are too large and manipulating them leads to arithmetic overflow.

Examples

extern crate itertools;

use itertools::Itertools;
use malachite_base::num::random::random_primitive_ints;
use malachite_base::random::EXAMPLE_SEED;
use malachite_base::vecs::random::random_ordered_unique_vecs_min_length;

let xs = random_ordered_unique_vecs_min_length(
    EXAMPLE_SEED,
    2,
    &random_primitive_ints::<u8>,
    6,
    1
);
let values = xs.take(20).collect_vec();
assert_eq!(
    values.iter().map(Vec::as_slice).collect_vec().as_slice(),
    &[
        &[11, 85][..],
        &[30, 32, 38, 90, 134, 136, 162, 166, 177, 200, 203, 217, 218, 223, 234, 235],
        &[9, 106, 151, 204, 213, 216],
        &[39, 78, 91, 97, 191, 253],
        &[170, 175, 232],
        &[2, 233],
        &[17, 22, 32, 35, 114, 198, 217],
        &[65, 114, 121, 173],
        &[25, 79, 144, 148, 173, 222],
        &[52, 115],
        &[34, 69, 73, 91, 112, 137, 153, 178],
        &[95, 106],
        &[167, 197],
        &[74, 86, 101, 115, 122, 130, 150, 168, 172, 177, 207, 218, 221],
        &[9, 48, 52, 109, 123, 133, 159, 201, 247, 250],
        &[196, 235],
        &[40, 68, 97, 104, 190],
        &[7, 216],
        &[11, 24, 43, 112, 157, 216, 217],
        &[29, 51, 55, 65, 84, 89, 103, 135, 191, 206, 211]
    ]
);